Nickel-alumina aerogel catalyst for carbon dioxide reforming of methane and the preparation method thereof

Abstract

The present invention relates to a method of containing nickel into the alumina aerogel prepared by sol-gel method and supercritical drying and of preparing the nickel-alumina hybrid aerogel catalyst. The nickel-alumina catalyst prepared in the present invention has an excellent reactivity with a prolonged lifetime.

What is claimed is:  
     
       1. A method of preparing an alumina aerogel support for a nickel-alumina catalyst comprising the steps of: 
       a first step of dissolving aluminum alkoxide in a heated alcoholic solvent;  
       a second step of adding a mixture of water, acid and alcohol into the thusly prepared solvent to form a transparent sol by partial hydrolysis;  
       a third step of cooling the transparent sol to room temperature and then adding alcohol containing water to the cooled sol to form a gel;  
       a fourth step of aging the gel;  
       a fifth step of supercritical-drying the aged gel; and  
       a sixth step of thermal-treating the dried gel initially in an inert atmosphere, and then in air or oxygen atmosphere.  
     
     
       2. The method according to claim  1 , wherein the temperature of the alcoholic solvent in the first step is maintained at 40° to 90° C. 
     
     
       3. The method according to claim  1 , wherein the aluminum alkoxide in the first step is aluminum isopropoxide or aluminum sec-butoxide. 
     
     
       4. The method according to claim  1 , wherein the aluminum/alcohol ratio in the first step is 0.4 to 0.6 mmol/ml. 
     
     
       5. The method according to claim  1 , wherein the water to aluminum ratio in the second step is 0.2 to 0.8 to form the transparent sol. 
     
     
       6. The method according to claim  1 , wherein the water to aluminum ratio in the third step is 0.5 to 1.5 to form a homogeneous gel in a short time. 
     
     
       7. The method according to claim  1 , wherein the initial thermal treatment of the supercritically dried gel in the sixth step is performed in an inert atmosphere at 200 to 500° C., and a secondary thermal treatment of the gel is performed at a temperature higher than 500° C. in air or in oxygen. 
     
     
       8. A catalyst composition comprising the alumina aerogel support material produced by the method of claim  1 , wherein said catalyst comprises 1% to 40% of nickel and 60% to 99% of alumina. 
     
     
       9. A method for making a catalyst composition by producing a support material according to the method of claim  1 , wherein there is a seventh step of impregnating nickel salt on the thermally treated gel from the sixth step. 
     
     
       10. A method of producing a nickel-alumina hybrid aerogel catalyst comprising the steps of: 
       a first step of dissolving aluminum alkoxide in a heated alcoholic solvent;  
       a second step of adding a mixture of water, acid and alcohol into the thusly prepared solvent and a further step of adding an alcohol solution containing nickel salt into the mixture to form a transparent sol by partial hydrolysis;  
       a third step of cooling the transparent sol to room temperature and then adding alcohol containing water to the cooled sol to form a gel;  
       a fourth step of aging the gel;  
       a fifth step of supercritical-drying the aged gel; and  
       a sixth step of thermal-treating the dried gel initially in an inert atmosphere and then in air or oxygen atmosphere.